54252

Appears in sequences

• a(n) = sum of all divisors of all numbers k such that n^2 <= k < (n+1)^2.at n=24A168012
• Rooted labeled Ptolemaic graphs on n nodes.at n=5A287885
• Number of nXn 0..1 arrays with every element unequal to 0, 1 or 2 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.at n=11A317758
• Irregular table read by rows: T(n,k) is the number of k-gons, k>=2, among all distinct circles that can be constructed from an n x n square grid of points when each pair of points is connected by a circle and the points lie at the ends of a diameter of the circle.at n=26A360354